Compact hairspray product consisting of hairspray concentrate, container and fine spray pump with pre-pressurization

ABSTRACT

The compact hair spray product includes a pressure-tight and diffusion-proof container containing a hair spray concentrate and equipped with a fine-spray pump with a cylindrical region made of a material that resists swelling by organic solvents. The fine spray pump has a maximum pump lift of 0.12 mL and pilot pressure buildup. The hair spray concentrate has a viscosity that confers good sprayability and contains at least one hair-strengthening polymer, an alcoholic solvent for the hair-strengthening polymer, at least one organic solvent additive capable of reducing the viscosity of the concentrate and increasing the vapor pressure of the concentrate and optionally a drying-retarding solvent additive.

BACKGROUND OF THE INVENTION

The object of the invention is a compact hair spray product comprising ahair spray concentrate, a pressure-tight and diffusion-proof containerand a fine-spray pump with pilot pressure buildup.

Hair spray products are usually sold either as aerosol sprays packed inaerosol containers and containing propellants or as propellant-free pumpsprays which are sprayed by means of a mechanical spray pump, the pumplift volume usually being 120-190 μL. Because of their betterperformance and better application properties, aerosol sprays aresubstantially more important. The conventional aerosol hair sprays,however, have the drawback that such products require relatively largeand unwieldy containers. This, in turn, leads to unattractive anddifficult-to-configure packaging forms. Commonly used, for example, are250-mL cans made of tinplate or aluminum in conventional cylindricalshape. The relatively large size is due to the comparatively large gasspace which is devoid of active substances and which is needed for thepropellant. Although pump sprays use no propellant and, hence, can besold in less voluminous packages compared to aerosol cans, one has toput up with a definite loss in application properties. Consumers feelthat, compared to aerosol sprays, the common, known pump sprays are forthe most part wetter and coarser and that they have a longer drying timeand a coarser drop spectrum. Their market share is correspondinglysmall. Moreover, because of the relatively low attainable concentrationof the hair-strengthening polymer in aerosol sprays and the need for alarge headspace, it has thus far not been possible to produce compactaerosol hair spray products which in terms of both applicationproperties and economy in use match the aerosol sprays in the usual250-mL package sizes.

Hair sprays are usually used in the form of polymer solutions in analcoholic medium. The polymer concentration is relatively limited.According to Schrader, “Grundlagen und Rezepturen der Kosmetika”[Fundamentals and Formulations of Cosmetics], 2nd edition, 1989, page772, the typical polymer content of a hair spray is 2-4%. Higher polymercontents lead to many problems which are due primarily to a markedincrease in viscosity of the composition. For example, when the polymerconcentration is increased, the droplet size of the sprayed compositionbased on the usual alcoholic solvent increases unacceptably to more than100 μm. Good pump hair sprays have an average droplet size of about 80μm, the smaller the better (for example 50 μm). The drawbacks ofexcessively large drops are the wetness effect, the pearl chain effectinvolving the formation of pearl-like droplets which on the hair arevisible, poorly flowing and poorly drying, moreover long drying times,poor distribution on the hair, deterioration of the spray pattern etc.Besides the average droplet size, the droplet size distribution isdetermining for the quality of a hair spray, because even a relativelysmall number of very large drops brings about major drawbacks. Thedv(50) and dv(90) values provide a measure of the droplet sizedistribution. These values give the maximum diameter of 50% or 90% ofall droplets. For typical aerosol hair sprays, the average dv(50) valueis about 40 μm and the average dv(90) value about 75 μm. For typicalpump hair sprays, the average dv(50) value is about 75 μm and theaverage dv(90) value about 120 μm. The dv(90) value, in particular,should not exceed 140 μm and preferably not 130 μm. The sprays willotherwise be perceived as being very wet.

European Patent EP 0 460 123 A discloses a one-phase solvent mixture ofC₂-C₄ alcohols, water and a lower alkane, selected from among n-pentane,n-hexane and isohexane. This solvent mixture can be used in non-aerosolhair sprays. Hair spray concentrates and compact hair sprays are notdescribed.

Desirable therefore are small, compact hair spray products whichcompared to the usual aerosol sprays and the usual pump hair sprayspresent a comparable economy of use at a fraction of the containervolume, while at the same time presenting application properties, forexample a strengthening efficacy and spray performance, that do not havethe drawbacks of common pump hair sprays, but approximate those ofaerosol sprays and, from the standpoint of environmental protection,also present a desirable, improved volatile organic compound [VOC]balance.

SUMMARY OF THE INVENTION

We have now found that this objective can be reached by use of a compacthair spray product comprising a special hair spray concentrate, apressure-tight and diffusion-proof container and a special fine-spraypump with pilot pressure buildup.

The object of the invention therefore is a compact hair spray productcomprising

(A) a hair spray concentrate having a viscosity permitting goodsprayability and containing

(a1) at least one hair-strengthening polymer,

(a2) an alcoholic solvent for polymer (a1),

(a3) at least one organic solvent additive capable of reducing theviscosity of the concentrate and increasing the vapor pressure of theconcentrate, and

(B) a pressure-tight and, for concentrate (A), diffusion-proof containerand

(C) a fine-spray pump with

(c1) a cylindrical region made of a material that resists swelling bythe organic solvent additive (a3),

(c2) a maximum lift of 0.12 mL and

(c3) pilot pressure buildup.

The hair spray concentrate preferably also contains a drying-retardingsolvent additive (a4).

The object of the present invention is eminently suited for theproduction of hair spray products of compact design, for example with avolume of 40 to 60 mL, presenting an economy of use approximating thatof typical 250-300 mL aerosol hair spray cans.

For purposes of the invention, by compact hair spray product is meant ahair spray product of more compact design than that of a typical aerosolhair spray, namely a product with a filling volume of less than 250 mLand particularly of at the most 150 mL. Preferred are filling volumesfrom 10 to 100 mL, particularly from 20 to 80 mL and especially from 40to 60 mL. For purposes of the invention, by hair spray concentrate ismeant a composition comprising at least one hair-strengthening polymerat a concentration that is higher than that of common hair sprays whichtypically is 4 wt. % and for hair lacquers 6 wt. %. The polymerconcentration is preferably higher than 8% wt. % and particularly higherthan 10 wt. %, based on the total composition. The maximum polymerconcentration is preferably 20 wt. %.

For purposes of the invention, by viscosity permitting good sprayabilityis meant a viscosity at which the average droplet size obtained with aSeaquist-Perfect PZ1/100 HVT fine-spray pump is less than 100 μm andpreferably less than 80 μm or for which the dv(90) value is at the most140 μm and preferably at the most 130 μm. The average droplet size anddroplet size distribution can be determined, for example, with the aidof a particle-sizing instrument based on laser radiation diffraction,for example a Malvern Particle Sizer instrument. The preferred kinematicviscosity is at the most 10 mm².s, and preferably at the most 5 mm².s,determined with a RheoStress 100 rotational viscometer, supplied byHaake, at a temperature of 25° C. and a shear gradient from 0.5 to 1400s⁻¹.

Suitable hair-strengthening polymers are selected from the groupconsisting of synthetic or natural or modified natural polymers, whichin each case can have a nonionic, cationic, anionic or amphotericcharacter. A mixture of several of these polymers can also be used.According to the invention, by hair-strengthening polymer is meant apolymer which when used in the form of a 0.01 to 5% aqueous, alcoholicor aqueous-alcoholic solution is capable of depositing a polymer film onthe hair thus strengthening the hair.

Suitable synthetic, nonionic, film-forming, hair-strengthening polymersare, for example, the homopolymers of vinylpyrrolidone, vinylcaprolactamor N-vinylformamide. Other suitable synthetic film-forming, nonionic,hair-strengthening polymers are, for example, the copolymers ofvinylpyrrolidone and vinyl acetate, the terpolymers of vinylpyrrolidone,vinyl acetate and vinyl propionate, polyacrylamide sold, for example, byCHEM-Y, Emmerich, under the tradename Akyponine® P 191 and by Seppicunder the tradename Sepigel® 305; polyvinyl alcohols sold, for example,by Du Pont under the tradename Elvanol® or by Air Products under thetradename Vinol® 523/540; and polyethylene glycol/polypropylene glycolcopolymers sold, for example, by Union Carbide under the tradenameUcon®.

Suitable natural or modified natural, film-forming polymers withhair-strengthening action are, for example, the chitosans with amolecular weight from 20,000 to about 5 million g/mol. Moreover, varioussaccharide types can be used, such as polysaccharides or mixtures ofoligo-, mono- and disaccharides, sold, for example, by Cerestar,Brussels, under the tradename C-PUR®. Other suitable natural polymersare Chinese balsamic resin, guar or guar derivatives and cellulosederivatives, for example hydroxypropylcellulose, with a molecular weightfrom 30,000 to 50,000 g/mol, sold, for example, by Lehmann & Voss,Hamburg, under the tradename Nisso S1®. Another natural polymer isshellac which can be used in neutralized, partly neutralized ornon-neutralized form.

Suitable anionic polymers contain acid groups that can be neutralizedwith appropriate bases. The acid groups are preferably selected fromamong —COOH,—SO₃H,—OSO₃H,—OPO₂H and —OPO₃H₂. Carboxylic acid groups areparticularly preferred. From 50 to 100% of the acid groups arepreferably in anionic or neutralized form. The neutralizing agent can beany organic or inorganic base suitable for cosmetic purposes. Examplesof bases are aminoalcohols, for example aminomethylpropanol (AMP),triethanolamine or monoethanolamine, and ammonia, NaOH etc.

The hair-strengthening anionic polymer can be a natural or synthetichomopolymer or copolymer with acid groups-containing monomer unitsoptionally copolymerized with comonomers devoid of acid groups. Suitablemonomers are unsaturated compounds capable of undergoing freeradical-initiated polymerization and which bear at least one acid group,particularly carboxyvinyl monomers. Suitable acid groups-containingmonomers are, for example, acrylic acid, methacrylic acid, crotonicacid, itaconic acid, maleic acid or maleic anhydride or a monoesterthereof, fumaric acid or a monoester thereof, aldehydocarboxylic acidsor ketocarboxylic acids. Other suitable anionic polymers are the anionicpolyurethanes.

Comonomers not bearing acid groups as substituents are, for example,acrylamide, methacrylamide, alkyl and dialkylacrylamide, alkyl anddialkylmethacrylamide, alkyl acrylate, alkyl methacrylate,vinylcaprolactone, vinylpyrrolidone, vinyl esters, vinyl alcohol,propylene glycol or ethylene glycol, amino-substituted vinyl monomers,for example dialkylaminoalkyl acrylate, dialkylaminoalkyl methacrylate,monoalkylaminoalkyl acrylate and monoalkylaminoalkyl methacrylate, thealkyl groups of these monomers preferably being C₁-C₇-alkyl groups andparticularly C₁-C₃-alkyl groups.

Suitable anionic polymers are, in particular, the following compounds,non-crosslinked or crosslinked with polyfunctional agents: homopolymersof acrylic acid or methacrylic acid, copolymers of acrylic acid ormethacrylic acid and monomers selected from among acrylate ormethacrylate esters, acrylamides, methacrylamides and vinylpyrrolidone,homopolymers of crotonic acid and copolymers of crotonic acid andmonomers selected from among vinyl esters, acrylate or methacrylateesters, acrylamides, methacrylamides and copolymers with polyethyleneoxide. A suitable natural polymer is, for example, shellac.

Preferred anionic polymers are crosslinked or non-crosslinked vinylacetate/crotonic acid copolymers (INCI¹ name: VA/crotonates copolymer)and vinyl acetate/crotonic acid/polyethylene oxide copolymers. Alsopreferred are the partially esterified copolymers of vinyl methyl etherand maleic anhydride, for example methyl vinyl ether/monoethyl maleateester or monobutyl maleate ester copolymer (INCI name: ethyl ester ofPVM/MA copolymer, butyl ester of PVM/MA copolymer). Other suitableanionic polymers are, for example, the copolymers of acrylic acid, alkylacrylates and N-alkylacrylamide (INCI name: acrylates/acrylamidecopolymer), particularly acrylic acid/ethylacrylate/N-tert.butylacrylamide terpolymers, and copolymers of one ormore C₁-C₅-alkyl acrylates, particularly C₂-C₄-alkyl acrylates andacrylic acid or methacrylic acid (INCI name: acrylates copolymer),particularly methacrylic acid/ethyl acrylate/butyl acrylate terpolymers.Also suitable are the terpolymers of vinyl acetate, crotonate and vinylalkanoate, particularly vinyl acetate/crotonate/vinyl neodecanoatecopolymers or vinyl acetate/crotonate/vinyl propionate copolymers (INCInames: VA/crotonates/vinyl neodecanoate copolymer andVA/crotonates/vinyl propionate copolymer).

¹ INCI=International Nomenclature of Cosmetic Ingredients—Translator

Suitable amphoteric polymers are those which besides acid or anionicgroups contain as additional functional groups basic or cationic groups,particularly primary, secondary, tertiary or quaternary amino groups.Examples of these are the copolymers derived from an alkylacrylamide(particularly octylacrylamide), an alkylaminoalkyl methacrylate(particularly tert.butylaminoalkyl methacrylate) and two or moremonomers consisting of acrylic acid, methacrylic acid or an esterthereof (INCI name: octylacrylamide/acrylates/butylaminoethylmethacrylate copolymer) supplied, for example, by NATIONAL STARCH, USA,under the tradename Amphomer® or Amphomer® LV-71. Other suitableamphoteric polymers are the copolymers derived from at least one monomerof the first kind containing quaternary amino groups and at least onemonomer of the second kind containing acid groups. Examples of suchcopolymers are the copolymers of acrylic acid, methyl acrylate andmethacrylamidopropyltrimethylammonium chloride (INCI: name:polyquaternium 47), such as those sold by Calgon under the tradenameMerquat® 2001, copolymers of acrylamidopropyltrimethylammonium chlorideand acrylates, for example those sold by Stockhausen under thecommercial name W 37194, or the copolymers of acrylamide,acrylamidopropyltrimethylammonium chloride, 2-amidopropylacrylamidesulfonate and dimethylaminopropylamine (INCI name: polyquaternium 43),sold for example, by Societe Francaise Hoechst under the tradenameBozequat® 4000. Also suitable are the polymers bearing betaine groups,for example the copolymers of methacryloylethylbetaine and two or moremonomers derived from acrylic acid or a simple ester thereof, knownunder the INCI name of methacryloyl ethyl betaines/acrylates copolymer.

Suitable polymers with basic groups preferably have a molecular weightof at least 50,000 g/mol and particularly from 100,000 to 6,000,000g/mol and they have nitrogen-containing groups, for example primary,secondary or tertiary amino groups. The basic polymers can be partly orcompletely neutralized with a suitable cosmetically compatible acid andthus be in the cationic form. Suitable acids are, for example, formicacid, pyrrolidonecarboxylic acid, lactic acid etc. The basic group iseither contained in the polymer chain or, preferably, is a substituentof one or several monomers. The polymer with basic groups can be anatural or synthetic homopolymer or copolymer with amine-substitutedmonomer units and optionally nonbasic comonomers. Suitable polymers withbasic groups are, for example, the copolymers of amine-substituted vinylmonomers and non-amine-substituted monomers. Amine-substituted vinylmonomers are, for example, dialkylaminoalkyl acrylate, dialkylaminoalkylmethacrylate, monoalkylaminoalkyl acrylate and monoalkylaminoalkylmethacrylate, the alkyl groups of these monomers preferably being loweralkyl groups such as, for example, C₁-C₇-alkyl groups and particularlyC₁-C₃-alkyl groups.

Non-amine-substituted comonomers are, for example, acrylamide,methacrylamide, alkyl and dialkyl acrylamide, alkyl and dialkylmethacrylamide, alkyl acrylate, alkyl methacrylate, vinylcaprolactone,vinylpyrrolidone, vinyl esters, vinyl alcohol, maleic anhydride,propylene glycol or ethylene glycol, the alkyl groups of these monomerspreferably being C₁-C₇-alkyl groups and particularly C₁-C₃-alkyl groups.

Suitable polymers with cationic groups preferably contain quaternaryamino groups. The cationic polymers can be homopolymers or copolymers,wherein the quaternary nitrogen groups are contained either in thepolymer chain or preferably as a substituent of one or more monomers.The ammonium groups-containing monomers can be copolymerized with theabove-said non-amine-substituted monomers. Suitable ammonium-substitutedvinyl monomers are, for example, trialkylmethacryloxyalkylammonium,trialkylacryloxyalkylammonium, dialkyldiallylammonium and quaternaryvinylammonium monomers with cyclic, cationic nitrogen-containing groups,such as pyridinium or imidazolium, or quaternary pyrrolidones, forexample alkylvinylimidazolium, alkylvinylpyridinium, oralkylvinylpyrrolidone salts. The alkyl groups of these monomers arepreferably lower alkyl groups, for example C₁-C₇-alkyl groups, andparticularly C₁-C₃-alkyl groups.

Suitable polymers with quaternary amino groups are, for example, thepolymers described in the CTFA² Cosmetic Ingredient Dictionary under thename polyquaternium, such as methylvinylimidazolium chloride/vinylpyrrolidone copolymer (polyquaternium 16), quaternizedvinylpyrrolidone/dimethylaminoethyl methacrylate copolymer(polyquaternium 11), homopolymers and copolymers ofdimethyldiallylammonium chloride (polyquaternium 6 and 7), quaternizedhydroxyethylcellulose (polyquaternium 10) or quaternized guarderivatives.

² CTFA=Cosmetics, Toiletry and Fragrance Association—Translator

Suitable among the cationic polymers that can be contained in thecomposition of the invention is, for example,polyvinylpyrrolidone/dimethylaminoethyl methacrylate copolymer. Othercationic polymers are, for example, the copolymer ofpolyvinylpyrrolidone and imidazolimine methochloride, the terpolymer ofdimethyldiallylammonium chloride, sodium acrylate and acrylamide, theterpolymer of vinylpyrrolidone, dimethylaminoethyl methacrylate andvinylcaprolactam, quaternized ammonium salts of hydroxyethylcelluloseand a trimethylammonium-substituted epoxide andvinylpyrrolidone/methacrylamidopropyltrimethylammonium chloridecopolymers.

Other suitable hair-strengthening polymers are the copolymers ofvinylpyrrolidone, vinylcaprolactam and a dialkylaminoalkylmethacrylamidewherein the alkyl groups preferably contain 1 to 3 carbon atoms.Particularly preferred are the terpolymers of vinylpyrrolidone,vinylcaprolactam and dimethylaminopropylmethacrylamide. (DMAPMA) sold byISP under the tradename Aquaflex® SF-40.

The hair-strengthening polymers preferred for the compact hair sprays ofthe invention are selected from among the copolymers of acrylates andacrylate hydroxyesters, copolymers of methyl vinyl ether and an alkylmonoester of maleic acid, copolymers of acrylic acid or methacrylic acidand an alkyl acrylate or alkyl methacrylate, copolymers of vinyl acetateand crotonic acid, copolymers of vinyl acetate and crotonic acid,copolymers of vinyl acetate, crotonic acid and vinyl alkanoates,copolymers of acrylic acid or methacrylic acid and an alkyl acrylate oralkyl methacrylate and an acrylamide or methacrylamide,polyvinylcaprolactam, vinylpyrrolidone/vinyl acetate copolymers,copolymers of vinylpyrrolidone, vinylcaprolactam anddialkylaminoalkylacrylamides or dialkylaminoalkylmethacrylamides,shellac, copolymers of alkylacrylamides, alkylaminoalkyl methacrylatesand two or more monomers consisting of acrylic acid, methacrylic acid oran ester thereof and acrylate/acrylamide copolymers and mixtures of saidpolymers. Particularly preferred among these are the hair-strengtheningpolymers selected from among acrylate/acrylamide copolymers, thecopolymers of alkylacrylamides, alkylaminoalkyl methacrylates and two ormore monomers consisting of acrylic acid, methacrylic acid or an esterthereof, copolymers of vinyl acetate and crotonic acid, copolymers ofvinyl acetate, crotonic acid and vinyl alkanoates, each in an amount of8 to 30 wt. %, and polyvinylpyrrolidone/vinyl acetate copolymers in anamount of more than 10 to 30 wt. %.

The hair-strengthening polymer is preferably used in an amount greaterthan 4 wt. %, more preferably greater than 8 to 30 wt. % andparticularly greater than 10 to 20 wt. %. The polymer is soluble ordispersible in the solvent mixture of the invention.

Suitable alcoholic solvents are C₁-C₄-alcohols, namely methanol,ethanol, isopropanol, n-propanol and butanol, of which ethanol andisopropanol are particularly preferred. The alcoholic solvent ispreferably used in an amount from 20 to 80 wt. %, more preferably from40 to 75 wt. % and particularly from 50 to 70 wt. %.

An essential component of the compact hair spray product of theinvention is an organic solvent additive which is liquid under normalconditions (20° C., 1013 mbar) and which reduces the viscosity of thehair spray concentrate while at the same time increasing the vaporpressure of said concentrate. This solvent additive is preferably usedin an amount from 1 to 50 wt. %, more preferably from 4 to 40 wt. % andparticularly from 8 to 30 wt. %. Suitable additives are, in particular,the linear, branched or cyclic C₅ or C₆ alkanes or mixtures thereof,namely n-pentane, isopentane, neopentane, n-hexane, or the branchedhexane isomers. Particularly preferred are the pentanes, particularlyn-pentane. These additives reduce the viscosity of the concentratedpolymer composition. A markedly higher-than-usual concentration isrequired to make a compact design possible. Because of the reducedviscosity of the hair spray concentrate, the resistance to flow isreduced when the spray pump is actuated so that more energy is availablefor atomizing the concentrate, which presumably is the reason for afiner spray and a reduced droplet size. As a result of the reduced vaporpressure of the overall composition, part of the solvent vaporizesspontaneously at the exit from the spray nozzle, which leads to afurther reduction in droplet size and better nebulization of the spray.The vapor pressure of the organic solvent additive must thus be higherthan that of the solvent used, but low enough to ensure that undernormal conditions the additive is in liquid form. When substances thatare gaseous at room temperature are used, a compact design is notfeasible because of the gas space required. Moreover, under normalconditions, gaseous substances such as the common propellants propaneand butane have the drawback that they vaporize immediately upon exitingthe nozzle so that essentially only the concentrate reaches the hair,said concentrate not flowing adequately on the hair because of itsviscosity.

Another preferred component of the compact hair spray product of theinvention is a solvent additive capable of retarding drying (a4).Without this additive, the sprayed-on composition dries too fast on thetreated hair, the sprayed-on composition does not flow sufficiently onthe hair and as a result the phenomenon known as the pearl chain effecttakes place. This means that only pointwise polymer depositions areobserved on the hair, and there is no sufficient film formation andcross-linking of the hair. Water is the preferred drying-retardingadditive. Other liquid, drying time-extending substances are alsoconceivable, for example polyhydric alcohols, such as, for example,glycols, such as ethylene glycol and propylene glycols, or glycerol oreven longer-chain alcohols. The drying-retarding solvent additive ispreferably used in an amount from 1 to 20 wt. %, more preferably from 2to 16 wt. % and particularly from 4 to 12 wt. %.

The hair spray concentrate according to the invention can containadditional, common cosmetic additives, for example plasticizers such asglycerol, glycol, phthalate esters or citrate esters, perfumes, perfumeoils, light-protective agents, UV filters, hair-care additives,combability improvers, moisturizers, dyes, corrosion inhibitors,antioxidants and preservatives, each in an amount from 0.01 to 10 wt. %,the total amount of additives ranging from 0.01 to 20 wt. %.

The container of the compact hair spray product of the invention can bemade of any material as long as the material is sufficiently resistantto the slightly elevated internal pressure, brought about by the vaporpressure-raising organic solvent additive, and sufficientlydiffusion-proof for the organic solvent additive. Suitable materialsare, for example, the metals usually employed for aerosol packages, suchas aluminum or tinplate. Preferred, however, are transparent or at leasttranslucent materials allowing the product consistency and/or amount ofcomposition in the container to be seen from the outside. The productcontainer is preferably made essentially of polyethylene terephthalate(PET)

The spray pump used for the compact hair spray product of the inventionhas a maximum lift of 0.12 mL, preferably from 0.075 to 0.115 mL andparticularly from 0.08 to 0.11 mL. Moreover, the spray pump is of thepilot pressure buildup design, meaning that when the pump is actuated,the pressure is allowed to build up before the spray is released. Thisresults in a finer spray and further reduction in droplet size.

The composition of the hair spray concentrate places specialrequirements on the material of which the spray pump is made. Thecylinder of a common spray pump for pump hair sprays is made of aplastic such as, for example, polypropylene, which can swell in contactwith the organic solvent additives, for example pentane. Such a standardpump fails after some time. According to the invention, a spray pump isused which in the cylinder region is made of a material that essentiallyresists swelling by the organic solvent additive. Such a material is,for example, polyoxymethylene (POM). A spray pump suitable according tothe invention is, for example, the Seaquist-Perfect PZ1/100 HVTfine-spray pump.

In contrast to the common spray pumps, a venting orifice is not needed,because the gas space formed upon emptying is filled by the highlyvolatile, evaporating organic solvent additive, and no air needs to beintroduced. Even though the presence of a venting orifice is acceptablebecause the slight loss of organic solvent additive, a pump without aventing orifice is preferred.

The compact hair spray product of the invention is characterized in thatit permits the production of hair spray products of compact design, thatcompared to conventional pump sprays it generates a less pronouncedwetness effect and dries in a shorter time, and that in terms ofapplication properties it approximates the conventional hair sprays. Itcan thus be viewed as a novel product type between a conventional pumphair spray and a conventional aerosol hair spray.

A few essential properties of a typical compact hair spray product ofthe invention are presented in the following table in comparison withthe properties of a common pump hair spray and a common aerosol hairspray.

Compact Pump Aerosol Hair Hair Hair Spray Spray Spray Polymer content,wt. % 10-20 3-8 2-6 Packing volume, mL 60 150 250 Amount applied, g 1.53.5 5.0 No. of applications/100 mL 52 24 14 Economy of use 4-fold 2-fold1-fold Applications/package 31 36 35 dv(50), μm about 78 about 80 about39 Drying time good poor good

Compared to the common pump spray, the compact spray of the inventionhas about twice the economy of use and shows substantially better dryingapproximating that obtained with an aerosol hair spray. Compared to acommon aerosol spray, the economy of use is even four times higher.

The following examples will illustrate the object of the invention ingreater detail.

EXAMPLES Example 1

Hair Spray Concentrate:

20.0 g of pentane 12.0 g of acrylates/acrylamide copolymer (Ultrahold ®8, BASF) 5.0 g of water 1.16 g of aminomethylpropanol 0.45 g of perfume0.36 g of dimethicone copolyol 0.36 g of triethyl citrate to 100 gethanol

The hair spray concentrate was charged to a tubular 40-mL container madeof translucent polyethylene terephthalate. The charged container wasprovided with a fine-spray pump, model Seaquist-Perfect PZ1/100 HVT,with a pump lift of 0.1 mL.

Example 2

Hair Spray Concentrate:

20.0 g of pentane 15.0 g of acrylates/acrylamide copolymer (Ultrahold ®8, BASF) 5.0 g of water 1.45 g of aminomethylpropanol 0.45 g of perfume0.45 g of dimethicone copolyol 0.45 g of triethyl citrate to 100 gethanol

The hair spray concentrate was charged to a tubular 60-mL container madeof translucent polyethylene terephthalate. The charged container wasprovided with a fine-spray pump, model Seaquist-Perfect PZ1/100 HVT,with a pump lift of 0.1 mL. The number of applications was close to thatfrom a 250-mL aerosol spray can. The following values were determinedfor the droplet size distribution: dv(50)=78 μm, dv(90)=109 μm.

Example 3

Hair Spray Concentrate:

20.0 g of pentane 12.0 g of vinyl acetate/crotonic acid/vinylneodecanoate terpolymer (Resyn 28-2930, National Starch) 5.0 g of water1.24 g of aminomethylpropanol 0.45 g of perfume 0.72 g of dimethiconecopolyol to 100 g ethanol

The hair spray concentrate was charged to a tubular 40-mL container madeof translucent polyethylene terephthalate. The charged container wasprovided with a fine-spray pump, model Seaquist-Perfect PZ1/100 HVT,with a pump lift of 0.1 mL.

Example 4

Hair Spray Concentrate:

20.0 g of pentane 15.0 g of VA/crotonates copolymer (Resyn 28-1310,National Starch) 5.0 g of water 1.55 g of aminomethylpropanol 0.45 g ofperfume 0.90 g of triethyl citrate to 100 g ethanol

The hair spray concentrate was charged to a tubular 60-mL container madeof translucent polyethylene terephthalate. The charged container wasprovided with a fine-spray pump, model Seaquist-Perfect PZ1/100 HVT,with a pump lift of 0.1 mL. The number of applications was close to thatfrom a 250-mL aerosol spray can.

What is claimed is:
 1. A compact hair spray product comprising a hairspray concentrate having a viscosity permitting good sprayability; apressure-tight and diffusion-proof container containing said hair sprayconcentrate; and a fine-spray pump associated with the pressure-tightand diffusion-proof container for spraying said hair spray concentrate;wherein said hair spray concentrate contains at least onehair-strengthening polymer; an alcoholic solvent for said at least onehair-strengthening polymer and at least one organic solvent additive;wherein said at least one organic solvent additive is liquid undernormal conditions, is capable of reducing viscosity of said concentrateand is capable of increasing vapor pressure of said concentrate; andwherein said fine-spray pump has a cylindrical region made of aswelling-resistant material, said swelling-resistant material resistsswelling by said at least one organic solvent additive, said fine-spraypump has a maximum lift of 0.12 mL and said fine-spray pump has pilotpressure buildup.
 2. The compact hair spray product as defined in claim1, containing greater than 10 percent by weight, based on saidconcentrate, of said at least one hair-strengthening polymer.
 3. Thecompact hair spray product as defined in claim 1, wherein said at leastone hair-strengthening polymer is selected from the group consisting ofcopolymers of acrylates and acrylate hydroxyesters; copolymers of methylvinyl ether and an alkyl monoester of maleic acid; copolymers of acrylicor methacrylic acid and alkyl acrylate or alkyl methacrylate esters;vinyl acetate/crotonic acid copolymer; copolymers of vinyl acetate,crotonic acid and vinyl alkanoates; copolymers of acrylic or methacrylicacid, alkyl acrylate or alkyl methacrylate esters and acrylamides ormethacrylamides; polyvinylcaprolactam; vinylpyrrolidone/vinyl acetatecopolymer; copolymers of vinylpyrrolidone, vinylcaprolactam and dialkylaminoalkylacrylamides or dialkylaminoalkylmethacrylamides; shellac;copolymers of alkylacrylamides, alkylaminoalkyl methacrylates and two ormore monomers, said monomers each consisting of acrylic acid,methacrylic acid or an ester thereof; and acrylate/acrylamide copolymer;and wherein alkyl groups of said copolymers each contain from one toseven carbon atoms.
 4. The compact hair spray product as defined inclaim 3, containing from more than 10 percent by weight to 30 percent byweight, based on said concentrate, of said at least onehair-strengthening polymer, and wherein said at least onehair-strengthening polymer comprises said vinylpyrrolidone/vinyl acetatecopolymer.
 5. The compact hair spray product as defined in claim 1,containing from 8 to 30 percent by weight, based on said concentrate, ofsaid at least one hair-strengthening polymer, and wherein said at leastone hair-strengthening polymer is selected from the group consisting ofacrylate/acrylamide copolymers; copolymers of alkylacrylamides,alkylaminoalkyl methacrylates and two or more monomers, said monomerseach consisting of acrylic acid, methacrylic acid or an ester thereof;copolymers of vinyl acetate and crotonic acid and copolymers of vinylacetate, crotonic acid and vinyl alkanoates; and wherein alkyl groups ofsaid copolymers each contain from one to seven carbon atoms.
 6. Thecompact hair spray product as defined in claim 1, wherein said alcoholicsolvent comprises at least one monohydric C₁-C₄-alcohol.
 7. The compacthair spray product as defined in claim 1, wherein said at least oneorganic solvent additive comprises at least one linear, branched orcyclic C₅-C₆ hydrocarbon.
 8. The compact hair spray product as definedin claim 7, wherein said at least one linear, branched or cyclic C₅-C₆hydrocarbon is selected from the group consisting of n-pentane,isopentane and neopentane.
 9. The compact hair spray product as definedin claim 1, further comprising a drying-retarding solvent additive. 10.The compact hair spray product as defined in claim 9, wherein thedrying-retarding solvent additive is water.
 11. The compact hair sprayproduct as defined in claim 1, wherein the pressure-tight anddiffusion-proof container is made of a transparent or translucentmaterial, so that the concentrate in the container is visible to anoutside observer.
 12. The compact hair spray product as defined in claim1, wherein the pressure-tight and diffusion-proof container is made ofpolyethylene terephthalate.
 13. The compact hair spray product asdefined in claim 1, wherein the cylindrical region of the fine-spraypump is made of swelling-resistant polyoxymethylene material.
 14. Thecompact hair spray product as defined in claim 1, wherein the lift ofthe fine-spray pump is from 0.08 to 0.11 mL.